Cleanup to use helper.

llvm-svn: 138369
diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 006cf5b..d2e5bc2 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -364,7 +364,7 @@
       continue;
 
     // Don't emit anonymous bitfields, they just affect layout.
-    if (Field->isBitField() && !Field->getIdentifier()) {
+    if (Field->isUnnamedBitfield()) {
       LastFD = (*Field);
       continue;
     }